The source of old Russian law named as "Ruskaia Pravda", being the essence of the article, shows a kind of look of Russian society at the edge of early and developed Middle Ages. The author tends to present hierarchy in relations of social categories established in first Russian entities, just as their structure caused by geopolitical influence of leading states of Scandinavia and Byzantine. The article begins with analyzing the external factors of creating initial steps of Russian statehood. It is followed by the author's pointing out of importance of Russian medieval legislative corner-stones to make importance of "Ruskaia Pravda" stressed out considering preserving of Russian society core values of that period. Substantially, the author pays attention to evidences quoted in "Ruskaia Pravda", as being special reflection of medieval man's understanding of social values just as being key factors of these values defending. Legal and institutional particularity of medieval Russia is illustrated by the author in this article by detailed overview of normative solutions placed in "Ruskaia Pravda", as one of the main governmental pillar having to do with forming early sociopolitical milieu of medieval Russia.